Lithium maintenance in both bipolar manic-depressive and schizo-affective outpatients. Efficacy in Manic and Schizo-affective Illness: a) Bipolar-manic depressives (or unipolar manics) and schizo-affectives not previously receiving drug maintenance: (1) Is lithium of greater prophylactic value than HAL or combined Li-HAL as a prophylactic treatment of manic relapses in manic-depressive or schizo-affective individuals? b) Bipolar manic-depressive patients previously on lithium maintenance: (1) Do those patients who continue to experience a manic relapse show a potentiation of the prophylactic effect of lithium by (1) Maintaining patients on lithium alone or (2) By adding haloperidol to the lithium regimen? a) Continued family history data in manic-depressives as well as schizo-affectives in efforts to further clarify any potential genetic implications in the effective illnesses: b) Continued exploration of an association between histocompatibility antigens (HLA system) and affective illness. The predictive potential of family history data as well as intracellular (RBC)-extracellular lithium levels for treatment outcome. Continued exploration of the neurological side effects of lithium maintenance.